This story is a bit down in the weeds, I’ll admit, but it has a bit of an interesting legal twist to it. Back in July, a duck boat sank on Table Rock Lake in Missouri, killing seventeen people, including nine members of a single family. It was a tragedy that made national headlines, but now the matter is making its way through the courts and an obscure law from the 1800s may put the captain of the boat in prison for a very long time. As the Washington Post reported this week, Captain Kenneth Scott McKee is looking at seventeen charges under what’s known as the “Seaman’s Manslaughter Statue” and could get ten years in prison for each one.

The statute that McKee was charged under is known colloquially as seaman’s manslaughter, and dates back to the era when steamboat disasters were commonplace, killing hundreds of people in fires and boiler explosions. In 1838, Congress passed legislation stating that captains and crew could be held criminally liable if anyone on board died as a result of their misconduct, negligence, or attention to their duties.

“Until recently, prosecutions under the Seaman’s Manslaughter Statute were a rare event,” Jeanne Grasso, a partner at Blank Rome LLP who specializes in maritime law, wrote in a 2005 article in Benedict’s Maritime Bulletin. From 1848 to 1990, she wrote, there had been only eight major prosecutions under the law. But between 1998 and 2005, the statute was used to prosecute boat captains and crew members in seven major cases.

At first glance, this may sound like a justifiable end to the story. The details of the sinking certainly made it sound as if the captain and crew were culpable. They set sail when terrible weather was clearly in the forecast, with high winds and lightning expected. When the storm struck, the captain failed to speed up and hasten toward shore to get his passengers out of it. When an alarm sounded, indicating that the ship was taking on water, the crew failed to direct them to put on life jackets. There was plenty of fault to be assigned, so why not charge the captain?

While I agree that he’s liable in at least some regards and bears the responsibility for the losses, this was still technically an accident. And in such a case the government generally has to prove negligence. But which kind? Normally, in order to convict someone of a crime equivalent to manslaughter and lock them up, the prosecutors must prove gross negligence. (That’s “a lack of care that demonstrates reckless disregard for the safety or lives of others, which is so great it appears to be a conscious violation of other people’s rights to safety.”) But because of this ancient law and the fact that it happened on a ship, the state only has to prove simple negligence. (That would be, “an injury that results from failing to take precautions that differs from negligence that is willful and deliberate.”)

Simply put, and as has already been pointed out by some legal scholars, you can be sent to prison for working on a ship and doing something which would probably only result in a fine if you did the same thing working on a train or a bus. Was the captain in this case grossly negligent? Failing to guess the weather correctly isn’t very easy to pin on him as it was impossible to say precisely how bad the storm would be until it arrived. His failure to speed up when it hit was a poor judgment call to be sure, but did it rise to the level of a reckless disregard for the lives of his passengers and crew? The failure to hand out the life jackets might qualify, but it’s a fine line.

The captain’s attorney has said that he will plead not guilty and fight this in court. But it sounds like unequal treatment under the law if he’s being held to a standard which only applies to sailing vessels and not ground or air transportation. That’s not to say he shouldn’t pay a price for the results of that terrible trip, but should he do more time than someone who murders a person with a gun over an accident? And should such a finding be based on such an archaic law? Stay tuned. We likely won’t know the answer until next year.